futex: Add Proton compatibility code

Signed-off-by: Simão Gomes Viana <[email protected]>

Author: andrealmeid

include/uapi/linux/futex.h

@@ -21,7 +21,7 @@
 #define FUTEX_WAKE_BITSET	10
 #define FUTEX_WAIT_REQUEUE_PI	11
 #define FUTEX_CMP_REQUEUE_PI	12
-#define FUTEX_WAIT_MULTIPLE	13
+#define FUTEX_WAIT_MULTIPLE	31
 
 #define FUTEX_PRIVATE_FLAG	128
 #define FUTEX_CLOCK_REALTIME	256

kernel/futex.c

@@ -4075,7 +4075,7 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
 			return -EINVAL;
 
 		t = timespec64_to_ktime(ts);
-		if (cmd == FUTEX_WAIT)
+		if (cmd == FUTEX_WAIT || cmd == FUTEX_WAIT_MULTIPLE)
 			t = ktime_add_safe(ktime_get(), t);
 		else if (!(op & FUTEX_CLOCK_REALTIME))
 			t = timens_ktime_to_host(CLOCK_MONOTONIC, t);
@@ -4278,6 +4278,7 @@ COMPAT_SYSCALL_DEFINE3(get_robust_list, int, pid,
  */
 struct compat_futex_wait_block {
 	compat_uptr_t	uaddr;
+	__u32 pad;
 	__u32 val;
 	__u32 bitset;
 };
@@ -4340,7 +4341,7 @@ SYSCALL_DEFINE6(futex_time32, u32 __user *, uaddr, int, op, u32, val,
 			return -EINVAL;
 
 		t = timespec64_to_ktime(ts);
-		if (cmd == FUTEX_WAIT)
+		if (cmd == FUTEX_WAIT || cmd == FUTEX_WAIT_MULTIPLE)
 			t = ktime_add_safe(ktime_get(), t);
 		else if (!(op & FUTEX_CLOCK_REALTIME))
 			t = timens_ktime_to_host(CLOCK_MONOTONIC, t);